Subclass of Struts's TilesRequestProcessor that autowires
Struts Actions defined in ContextLoaderPlugIn's WebApplicationContext
(or, as a fallback, in the root WebApplicationContext).

Behaves like
DelegatingRequestProcessor,
but also provides the Tiles functionality of the original TilesRequestProcessor.
As there's just a single central class to customize in Struts, we have to provide
another subclass here, covering both the Tiles and the Spring delegation aspect.

The default implementation delegates to the DelegatingActionUtils
class as fas as possible, to reuse as much code as possible despite
the need to provide two RequestProcessor subclasses. If you need to
subclass yet another RequestProcessor, take this class as a template,
delegating to DelegatingActionUtils just like it.